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Observing Beneath the Shadows of Jupiter

Once again for my 13th year I attended our club’s annual dark-sky observing expedition. This event takes place in western mid-state Wisconsin during the summer months at Wildcat Mountain State Park. With its very rural location and respectable elevation for the Midwest, moonless clear nights with excellent transparency can reward the visually and knowledgeably acute astronomer with limiting magnitudes approaching seven.

This year at Wildcat Mountain was no exception to that rule. Of the two weekend nights that I could attend, Friday, August 1st was the one of those memorable nights that forever is etched in ones memory due to an exceedingly dry air mass that settled over our location. When I left my home in northern Illinois around 1pm to begin the four-hour trek to ‘the mountain from which the stars reign as king’ the weather conditions were hazy, hot and humid. However as I traveled northwest conditions improved rapidly. By the time I arrived at my destination the humidity/dew point had dropped considerably, and the skies showed signs of great transparency for the approaching night.

As the Sun started to set behind a row of trees to my west, I began to assemble my 20” Obsession telescope. This is my 10th year into ownership of that instrument, and it was only fitting that this decade long anniversary could have been blessed with such great observing conditions.

As I looked upon the observing field, I became impressed with the formidable array of instrumentation lined up. In this array were several 10” Newts, two C-14s, two 16” dobs, a 17.5” dob, three 20” dobs, a 12.5” Ritchey-Chretien CCD imaging instrument, and several other smaller SCTs. Most importantly though was the presence of about 20 very motivated Earthlings eager to commence observing activities at nightfall.

Once twilight had completely subsided many of us had to back away from instruments and just take in the naked eye view of the entire night sky. The transparency of the air above was about as good as it gets at that location. The summer Milky Way arched over our heads appearing like a structural, supporting beam in some ridiculously gigantic celestial cathedral. The intensity of its brightness did not wane at all whether or not you viewed it at zenith or near the horizon. The view resembled Terrance Dickinson’s ‘Back Yard Astronomer’ book in which depicts a beautiful timed exposure of the summer Milky Way stretching behind a row of trees on its cover.

As the title of this article announces, Jupiter was astonishingly bright. Its brightness, undoubtedly a result of its surrounding ultra-black sky, produced shadows from ground fixed objects. Once the planet reached the meridian I noticed this strange affect walking away, and then back to the observing field from where my camper was located. And outstretched hand in front of any lightly colored surface; i.e. a telescopes white OTA, produced a shadow that was distinct enough to ‘almost’ allow the observer to count ones fingers! Additionally, in an ironic twist, the celestial light from Jupiter was bright enough to rob your dark adaptation if gazed upon for too long.

While observing amidst Jupiter’s shadows, intense DSO observing began. With a 13mm Ethos eyepiece firmly placed in my telescope, I began surveying all of the obvious DSOs in Sagittarius. While beginning with M-8 and the Triffid Nebula, I began panning northward. First of all let me say that M-8 naked eye appeared almost as it does in a 50mm pair of binoculars in that it’s linear shape was very obvious. The view of M-8 with the 13mm Ethos in those dark skies rendered the need for an interference filter completely moot. Detail in the interstellar dust and gas showed distinct striations with bluish-green colors saturating the entire view. That photographic ‘stellar bridge’ to the Triffid nebula was very obvious. As I panned northward I abruptly collided with the Omega Nebula and was nearly knocked off my ladder. Again a nebula filter was utterly unneeded, and like M-8, striational detail was abound Next to the star clouds. I replaced my 13mm Ethos with the 31 Nag. Wow, totally 3-D like! You could easily trace the outside of these clouds and see their true periphery instead of the typical ‘pan to gray’.

Pegasus was now rising decently, and with the 13 Ethos back in place, I traveled northeasterly to NGC 7331. At first glance I was floored in that the galaxy seemingly stretched across the entire .5 degree field in my scope’s view. Closer inspection revealed that it didn’t of course, but the mottling and structure in the galaxy’s spiral arms was awesome. Four other galaxies were obvious in the same view, 3 of which formed a lose triangle above the galaxy’s view in the eyepiece. I then slided the scope eastward a ran square into that ghostly quintet known as Stephans. All five galaxies were readily apparent and were noticeably brighter and more distinct then I ever remember seeing them before. I spent a good 30 minutes just staring at that view trying to figure just how it was positioned with respect to my location in the Milky Way. Now it was back southwest to that cool pair of edge-on galaxies, one of which being NGC 7332. Another first for sure, that is in how resolved the pair was.

Now for the showstoppers, M-31 and M-33. M-33 appeared absolutely photographic, but again better as it was in real-time. Its pinwheel shape was blatantly obvious and its H2 regions, all there, were very apparent. One could easily trace its spiral arms with direct vision all the way to the galaxy’s outer edges. M-31was colorful; plain and simple. Several other observers and myself noticed a pinkish, reddish, bluish color directly outside the nucleus spreading outward towards the galaxy’s insanely obvious dust lanes. With the galaxy nearly overhead I quietly sat on top of my ladder and just stared at that object for nearly 20 minutes panning back and fourth trying to imagine what it would be like to be in some futuristic inter-galactic spaceship viewing the galaxy from a much closer distance.

Probably the most astounding view that demonstrated the superb nature of that location’s night sky, and usage of highly optimized Instrumentation was the view of the Perseus galaxy cluster. Using the 13mm Ethos in a 20” dob, nine galaxies were easily seen in it’s .5 degree field at nearly 200X. Surprisingly bright, some of the galaxies showed distinct structure with great character. As I’m sure many of you know, the Perseus cluster lies some 320 million light years away! That’s HARDCORE deep-field viewing, and could only be done successfully in skies of Wildcat’s class.

Near the end of the evening, in the early morning hours, approximately 4:45am, only 4 of us were left standing. To the east twilight of the approaching day had begun. We quickly began observing objects in Taurus and Auriga but quickly ran out of energy as the sky grew lighter and lighter. Thoughts of some kind of sleep before the summer heat blew us out our tents and campers became overwhelming thus ending our first night at Wildcat Mountain at the place where stars reign as king!